On December 18, 2019, after weeks of discussions among legislators, the House of Representatives vote to impeach the 45th President, Donald Trump, for abuse of power and obstruction of Congress. The vote fell largely along party lines: 230 in favor, 197 against and 1 present. Trump became only the third president ever to be impeached, joining Andrew Johnson and Bill Clinton, after concerns about his alleged attempts to seek foreign interference in the 2020 election.

Some Democrats had advocated impeaching Trump since the moment of his election. After they regained control of the House of Representatives, Democrats launched multiple investigations into his business dealings and his campaign's ties to Russian hackers who targeted his 2016 opponent, Hillary Clinton. After an exhaustive effort failed to convince Speaker Nancy Pelosi and others that they had reason to impeach, a new scandal emerged that succeeded in doing so.

In September 2019, the public learned of a whistleblower complaint regarding a July phone call between Trump and Ukrainian President Volodymyr Zelensky. The complaint, which was corroborated by the acting Ambassador to Ukraine, stated that Trump had threatened to withhold U.S. foreign aid money until Zelensky promised to investigate Hunter Biden, son of leading Democratic 2020 candidate Joe Biden, for suspicious dealings in Ukraine.

The White House denied any "quid pro quo." Nonetheless, by late November, it was clear that the Democrats felt confident enough in their case for wrongdoing and obstruction of Congress that they would go through with impeachment.

After both articles were approved in the House, the case then moved to a Senate trial, which began on January 16, 2020. U.S. Supreme Court chief justice John Roberts presided over the trial. On February 5, 2020, in a vote that again fell largely along party lines, the Senate voted to acquit President Trump on both charges.

On January 13, 2021, President Trump was impeached again following the January 6, 2021 riot at the U.S. Capitol, becoming the only U.S. president to be impeached twice. Unlike his first impeachment, 10 House Republicans joined Democrats in voting in favor of impeachment. The former president was found not guilty in the Senate trial, though seven Republican senators joined Democrats in voting to convict.